HIT - Happenings in Tech: How QR Code Works

First of all QR Code stands for 'Quick Response Code' , As a name suggest quick response meaning after scanning through device you get data in a blink of an eye. For storing large amount of data into QR has no weightage because we cannot send large enough data to QR system so there is a boundation in terms of storing data as maximum it can store up to 40K alphanumeric data.

What are QR Codes and it's Uses?

Basically QR code is a 2-dimensional matrix of pixel which can store two pixels whether 1 or 0 you could also think like that for darker color it will store 1 and for lighter color it will store 0 to it. Now when you use hardware device for getting the data from QR then device will convert these 0's and 1's to data.

This technique will encode the alphanumeric data with series of pixels Now we want some guy in between to let us know what was that encoded data so for this QR Scanner and Camera Application came into picture Sounds Good!, Now these hardware devices decode the series of pixels to back to human readable form.

The Japanese company Denso Wave, a Toyota subsidiary, was invented first QR code system in 1994. They needed a more accurate way to track vehicles and parts during the manufacturing process. To achieve this, they developed a type of barcode system that could have encode hiragana, kanji, katakana, and alphanumeric characters.

QR acts a database but you cannot store large amount of data to it so there is limit on data you can store atmost 7089 alphanumeric data to it by using Model 2 but if you want to store 1167 alphanumeric data then you should use Model 1.

The data store by QR can include alphanumeric data, URL's, Digits, Binary data, Control Code and any random data. QR can perform these operations like direct downloadable link of your company app, to access your company information, direct watch link for your YouTube channel, google drive link for any particular files, send and receive payments in one shot.

Initially the idea of QR is like new planted seed, It was in 2002 that use of the code became widespread among the general public in Japan. What facilitated this trend was the marketing of mobile phones with a QR Code-reading feature. These phones make it possible for people to access a website by scanning a strange, eye-catching pattern.

Planted seed was soaring every day, In 2020 Denso Wave updated their original design to new one. Their new QR codes include traceability, brand protection, and anti-forgery measures. Denso wave made their QR code publicly available that means now everyone will use this as a free product and implement their idea with new concepts.

Algorithms used in QR?

QR works as database to store limited data into it in the series of pixels. To generate a QR code out of text-data, an encoding is used. There are many encoding available depending on characters used and length of text data then for human readable format we need to decode this 0's and 1's to data then we use camera app or any other hardware device.

The encoding converts a text data into a stream of 0's and 1's depending on which encoding was used also gives image width and height in pixel. Then an image drawing algorithm just prints a dark pixel when it finds 1 in the generated stream and light pixel when it finds 0. Input to this drawing algorithm is the stream of 0's & 1's and height & width of the image.

Features of QR code?

1. Encoding a large amount of data with a small code : QR can encode alphabetical characters, kanji characters, katakana and hiragana characters, symbols, binary data, control codes and other data.

2. Resistant to dirt and damage : Since QR codes have an error correction function, data can be restored even if a code is partially stained/missing.

3. Printing in a square area : Since QR Codes encode data in the transverse and longitudinal directions, a QR code can represent data using approximately 10 times less space than a traditional barcode.

4. Readable regardless of the scanning angle : QR can be read at high speed regardless of the scanning angle. The secret lies in three position detection patterns, which are located in each code, enabling stable high-speed reading without being affected by the background patterns.

Types of QR code

1. Model 1/ Model 2 : The QR Codes started with the model 1 and quickly evolved, upgrading to model 2. The main difference of model 1 and model 2 is the addition of the alignment pattern, which gives it higher capacity. Model 1 could hold up to 1167 alphanumeric characters, while model 2 can reach up to 7089 alphanumeric characters. One alphanumeric character is either a character from A to Z or a number from 0 to 9 and any other data are stores in such small logic system.

2. Micro QR code : This QR system stores only 35 alphanumeric data so for storing less amount of data then you should go with this type.

3. IQR code : Now QR can be generated either in horizontal or in vertical format. which stores 40000 alphanumeric data into this system.

4. SQRC : QR can be used for storing personal data like bank information, credit card information and much more. This QR system is same as normal QR code which is model 1/Model 2.

5. Frame QR : Now images are also accepting in this QR system with data. Frame QR is used for various purposes like sales promotion.

Meaning of Square and 3 squares on QR

Basically, a QR code works in the same way as a barcode at the supermarket. Every QR code consists of a number of black squares and dots which represent certain pieces of information. When your Smartphone scans this code, it translate that information into something that can be easily understand

by humans.

The 3 squares are position markers. They allow the QR code reader to quickly identify and orient that image in order to scan it. The small square is for alignment: This detects any curvature or distortion to the code and allows the reader to make corrections as needed.

Below is the image information for 3 squares, small squares and much more.

Quiet Zone : This zone you see in image is borders of QR code. This will ensure for optimum and fast scan.

Format Information : Contains information regarding the mask for the code and error correction.

Version Information : There are various different versions of the QR code standard; the version information (positioned near two of the finder patterns) simply identifies which one is being used in a particular code.

Position : The three position markers allows the QR code reader to quickly identify and orient that image in order to scan it.

Alignment Patterns: if anyway QR damages the also this will detects the QR. This detects any curvature or distortion to the code and allows the reader to make corrections as needed.

Timing Patterns : This will determine coordinates of QR and runs horizontally and vertically between the three finder patterns and consists of alternate black and white squares. The timing pattern makes it easy to identify the individual data cells within a QR code and is especially useful when the code is damaged or distorted.